There are few epidemiologic data on invasive bacterial infections among children in sub-Saharan Africa. We studied every acute pediatric admission to a rural district hospital in Kenya to examine the prevalence, incidence, types, and outcome of community-acquired bacteremia. Between August 1998 and July 2002, we cultured blood on admission from 19,339 inpatients and calculated the incidence of bacteremia on the basis of the population served by the hospital. Of a total of 1783 infants who were under 60 days old, 228 had bacteremia (12.8 percent), as did 866 of 14,787 children who were 60 or more days of age (5.9 percent). Among infants who were under 60 days old, Escherichia coli and group B streptococci predominated among a broad range of isolates (14 percent and 11 percent, respectively). Among infants who were 60 or more days of age, Streptococcus pneumoniae, nontyphoidal salmonella species, Haemophilus influenzae, and E. coli accounted for more than 70 percent of isolates. The minimal annual incidence of community-acquired bacteremia was estimated at 1457 cases per 100,000 children among infants under a year old, 1080 among children under 2 years, and 505 among children under 5 years. Of all in-hospital deaths, 26 percent were in children with community-acquired bacteremia. Of 308 deaths in children with bacteremia, 103 (33.4 percent) occurred on the day of admission and 217 (70.5 percent) within two days. Community-acquired bacteremia is a major cause of death among children at a rural sub-Saharan district hospital, a finding that highlights the need for prevention and for overcoming the political and financial barriers to widespread use of existing vaccines for bacterial diseases.

The 13-valent pneumococcal conjugate vaccine (PCV13) protects against key serotypes that increased after routine immunisation with the seven-valent vaccine (PCV7), but its potential for herd protection and serotype replacement is uncertain. The aim of this study was to analyse the effect of the 13-valent pneumococcal conjugate vaccine on invasive pneumococcal disease in England and Wales 4 years after its introduction. We used a national dataset of electronically reported and serotyped invasive pneumococcal disease cases in England and Wales to estimate incidence rate ratios (IRRs) for vaccine and non-vaccine type invasive pneumococcal disease between July, 2013, and June, 2014, versus the pre-PCV13 and pre-PCV7 baseline. Incidence rates were corrected for missing serotype data and changes in surveillance sensitivity over time. An over-dispersed Poisson model was used to estimate IRRs and confidence intervals. Incidence of invasive pneumococcal disease in the epidemiological year 2013/14 decreased by 32% compared with the pre-PCV13 baseline (incidence 10·14 per 100,000 in 2008-10 vs 6·85 per 100,000 in 2013/14; IRR 0·68, 95% CI 0·64-0·72). This was due to an 86% reduction of the serotypes covered by PCV7 (1·46 vs 0·20 per 100,000; IRR 0·14, 0·10-0·18) and a 69% reduction of the additional six serotypes covered by PCV13 (4·48 vs 1·40 per 100,000; IRR 0·31, 0·28-0·35). When compared with the pre-PCV7 baseline, there was a 56% overall reduction in invasive pneumococcal disease (15·63 vs 6·85 per 100,000; IRR 0·44, 95% CI 0·43-0·47). Compared with the pre-PCV13 baseline, the incidence of non-PCV13 serotypes increased (incidence all ages 4·19 vs 5·25 per 100,000; IRR 1·25, 95% CI 1·17-1·35) due to increases across a broad range of serotypes in children younger than 5 years and in people aged 45 years or more. In children younger than 5 years, incidence of non-PCV13 serotypes in 2013/14 was higher than in 2012/13 (age <2 years: 12·03 vs 10·83 per 100,000; age 2-4 years: 4·08 vs 3·63 per 100,000). 8 years of PCV use in England and Wales has reduced the overall incidence of invasive pneumococcal disease by more than 50%. The herd protection induced by PCV7 is continuing, and similar indirect protection is occurring from the additional serotypes covered by PCV13. There is, however, evidence of increasing invasive pneumococcal disease due to non-PCV13 serotypes, particularly in children younger than 5 years in 2014. If this increase continues, the maximum benefit of the PCV13 programme in children might already have been achieved. Public Health England funds national surveillance of invasive pneumococcal disease.

[3H]tobramycin bound to sodium alginate and to exopolysaccharide prepared from two mucoid strains of Pseudomonas aeruginosa. Binding to sodium alginate was similar to binding to exopolysaccharide, both in the dependence on tobramycin concentration and in the maximum binding observed at saturation. Incorporation of sodium alginate into agar plates reduced the zone sizes of growth inhibition caused by tobramycin. The reductions in zone sizes were quantitatively accounted for by the binding of tobramycin to sodium alginate during diffusion of the antibiotic away from the well in which it had been placed at the start of the experiment. However, the binding of tobramycin to the exopolysaccharide of P. aeruginosa, and the resulting inhibition of diffusion of the antibiotic, did not significantly increase the penetration time of a spherical microcolony with a radius of 125 micron, such as might be found in the respiratory tract of a patient with cystic fibrosis (from a 90% penetration time of 12 s in the absence of exopolysaccharide to one of 35 s with an exopolysaccharide concentration of 1.0% [wt/vol]).